The present invention relates to a bolt with shearable head according to the generic term of claim 1.
Today bolts with shearable head are used e.g. in screw connections or screwed cable lugs for clamping cables or wires.
From EP-A-0 470 388 a bolt with shearable head is prior art, having an external thread section, a head section, a taper section with a predetermined breaking point, arranged in between the external thread section and the head section, as well an end section providing a clamping contact.
The external thread section is here screwed into a corresponding internal thread section of a screw connection or screwed cable lug, into which a conductor has been inserted, which shall be clamped by the bolt with shearable head.
In order to guarantee a defined tightening moment in agreement with the relevant provisions, the bolt with shearable head has a predetermined breaking area in form of a predetermined cross section, breaking away from the thread section at a predetermined torque applied to the head section.
By means of the bolt with shearable head of the above mentioned state of the art a satisfactory result for clamping the relevant conductor may be reached.
However, the individual conductors connected to the screw connectors or screwed cable lugs are of different sizes, depending on the relevant transmission power and/or strength of the conductor. This means that a variety of differnt screw connectors is required, in turn requiring bolts with shearable head of different dimensions. The variety of bolts with shearable head results in higher costs for each individual bolt and leads to problems concerning the application safety as the danger of confusion is increased.